Football would not look like it does today without Ray Flaherty, the Boston/Washington Redskins coach who with the help of Sammy Baugh, introduced the behind-the-line screen pass to the sport in the 1937 NFL title game against the Bears. But that wasn't the only innovation the legendary coach introduced to the league. He also was the first coach to utilize a two-platoon system, one unit for passing, the other unit emphasizing the run. Flaherty ended up winning two NFL championships with the Redskins and his overall coaching run totaled an impressive 80-37-5 mark.

22. Hank Stram

A true innovator of the sport, Hank Stram was the man behind such things as the two tight end offense, the moving pocket, and the stack defense. He is also the only AFL coach to lead his team to two Super Bowls, and his win in Super Bowl IV helped earn credibility and respect to the fledgling league. Throughout his 17 year head coaching career, Stram earned a record of 131-97-10, and is still remembered as one of the key figures in Chiefs history.

21. Dick Vermeil

The coach who proved it's okay to cry, Dick Vermeil was so burned out in 1982 he abruptly quit coaching only to comeback 15 years later and take over the Rams, a move that would not only win him a Super Bowl, but cement his legacy as one of the few coaches able to step away for any prolonged period of time and still find success. After winning the Super Bowl, Vermeil walked away from the game again, only to come back for one last run with the Kansas City Chiefs before finally retiring for good after the 2005 season. If there was ever a coach players loved to play for, it was Vermeil, the kind of coach who added heart to his hard work and was never afraid to get emotional when it came to standing up for the players he loved.

Check back to IGN Sports next week as we continue our countdown of the greatest coaches of all time.